Nausea and vomiting in the first trimester of pregnancy is a common problem affecting 2/3 of pregnant women. This symptom complex is poorly understood and very few prospective studies with objective physiologic data have been performed. Recent studies have shown that the nausea and vomiting of pregnancy correlates with disturbances in the gastric slow wave of the stomach. The proposed study will assess which nutritional components worsen or improve gastric dysrhythmias and symptoms of nausea and vomiting in the first trimester of pregnancy.